WHERE TO DROP FOR UNPLAYABLE LIE UNDER THE LIP OF A BUNKER

The Rules of Golf define a bunker as a hazard consisting of a prepared area of ground, often a hollow, from which the turf has been removed and filled with sand. Grass covered ground bordering or within the bunker is not a part of the bunker. The margin of the bunker extends vertically downwards, but not upwards. Furthermore, A ball is in the bunker when any part of it touches the bunker.

So, according to the rules, your ball is not in the bunker if it is under the concave lip of a bunker, as shown here.

This is important to know if you decide to call the ball unplayable. When you take an unplayable lie for a ball that is in a bunker, you must drop the ball in the bunker, either within two clublengths no closer to the hole or on a line going back from the hole through where the ball lay. Your only other option is to return to the point where you hit your previous shot from and take the stroke and distance penalty.

Since the ball in figure "A" above is not in the bunker, you cannot drop your ball in the bunker. You may drop within two clublengths of where the ball lies, no closer to the hole (if there is such a point). Or you can drop behind the bunker on a line that goes from the hole through where the ball lies. Of course you may also elect to take the stroke and distance penalty.

Below is another situaion that is very similar to the one above. The ball is plugged in loose sand under the lip of the bunker.
In this situation the ball has become completely embedded in the vertical lip of the bunker. You might look at it and think that your ball is not in the bunker because it has gone beyond the vertically downward plane of the lip. However, this is not the case because an embedded ball is considered to be lying in the part of the course where it entered the ground.

So, if your ball is situated such as the one in figure "B", you may not invoke the imbedded ball (as I have seen people try) and you must drop the ball in the bunker if you declare it unplayable, unless you take the stroke and distance penalty.

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